The clashes around Ghazni, some 130 km (80 miles) southwest of Kabul, underlined the worsening security situation across Afghanistan, where national soldiers and police are struggling to cope now the bulk of foreign forces have withdrawn.

Monday’s violence followed days of sporadic fighting near Ghazni, and prompted most shops, schools and universities there to close.

Many residents attempted to flee to the capital Kabul or nearby districts, adding to a growing number of internally displaced people within Afghanistan.

“Hundreds of Taliban attacked from two directions and the fighting is still on some 7 km away from the provincial capital,” Ghazni’s Deputy Governor Mohammad Ali Ahmadi told Reuters. “The Taliban planned to attack and seize the capital but we were on the alert and repelled them,” he said.

The hardline Islamist militant movement, seeking to topple the Western-backed government in Kabul and restore its regime 14 years after being toppled, also said it had blocked the highway from Kabul to the southern city of Kandahar.

The Taliban warned motorists to avoid the key transport corridor linking the capital to the south, which was rebuilt with the help of Western aid. There was no independent confirmation of their claim to have blocked the route.

Earlier on Monday, a local UN staffer was shot and killed by two gunmen on a motorbike as she was on her way to work in Kandahar. “She was fatally wounded and later died in hospital,” said Mujib ur Rahman, a UN press officer in Kandahar.

On Sunday, a suicide bomber attacked a convoy of foreign troops during Sunday morning rush hour in Kabul, wounding at least three civilians.

Since the withdrawal of international troops from most combat operations at the end of last year, the brunt of fighting has been borne by Afghan forces. Any hopes of a negotiated settlement with the Taliban were dealt a blow earlier this year, when a power struggle broke out following confirmation that the movement’s founder, Mullah Omar, had died two years earlier.

Under new leader Mullah Akhtar Mansour, the Taliban have mounted a wave of attacks in Kabul and beyond, culminating in the seizure of Kunduz in a carefully orchestrated offensive. While some areas in mountainous regions near Pakistan and in the southern province of Helmand have long been under the control of the Taliban, the fall of once sleepy Kunduz, some 230 km (150 miles) from Kabul, represented a sharp escalation.

It was the first time the Taliban, which imposed harsh Islamic law when in power including public executions and denying women the right to education and work, had taken a major provincial capital since 2001. Government forces have since wrested back control of most of Kunduz.

It was also a stark warning of how far the Taliban has extended its reach into regions once thought secure, stretching government forces and piling pressure on President Ashraf Ghani’s fragile national unity government.

The worsening violence has caused alarm in Washington, where President Barack Obama must decide on whether or not to stick to an earlier decision to cut US troop levels in Aghanistan to a small US embassy-based force after 2016.